Apparatus, system, and method for vasculature obstruction removal

ABSTRACT

An obstruction removal device is configured to be inserted through a catheter and at least partially extended into a vasculature from a distal end of the catheter. The obstruction removal device includes: a base member configured to engage one or more guide stops at the distal end of the catheter; a tubular member coupled to the base member and configured to apply a suction force from the catheter to an obstruction to remove the obstruction from the vasculature; and an expandable member surrounding the tubular member. The expandable member is configured to transition from a contracted state to an expanded state after the expandable member is at least partially extended into the vasculature from the distal end of the catheter. The expandable member is further configured to at least partially surround the obstruction as the obstruction is being removed from the vasculature.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit under 35 U.S.C. § 119(e) ofU.S. Provisional Application No. 63/140,433, filed Jan. 22, 2021, andtitled “APPARATUS, SYSTEM, AND METHOD FOR VASCULATURE OBSTRUCTIONREMOVAL.” The present application is also a continuation-in-part of U.S.Nonprovisional application Ser. No. 16/572,150, filed Sep. 16, 2019, andtitled “APPARATUS, SYSTEM, AND METHOD FOR VASCULATURE OBSTRUCTIONREMOVAL,” which claims the benefit of U.S. Provisional Application No.62/767,852, filed Nov. 15, 2018, and titled “APPARATUS, SYSTEM, ANDMETHOD FOR VASCULATURE OBSTRUCTION REMOVAL.” Each of the relatedapplications is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention generally relates to medical devices, and, moreparticularly, to medical devices for removing vascular obstructions.

BACKGROUND

Obstruction removal systems/devices may operate by lodging theobstruction in a component of the removal system. In some cases, theobstruction may dislodge. Dislodgement of the obstruction substantiallyincreases the risk for potential complications, such as stroke or heartattack. Thus, it is desirable to secure the obstruction safely forremoval from the body.

SUMMARY

An obstruction removal system, device and method are disclosed.

In one or more embodiments, an obstruction removal system includes acatheter and an obstruction removal device. The catheter is configuredto be inserted within a vasculature. The catheter may have one or moreguide stops located at a distal end of the catheter. The obstructionremoval device is configured to be inserted through the catheter and atleast partially extended into the vasculature from the distal end of thecatheter.

In one or more embodiments, an obstruction removal device includes: abase member configured to engage one or more guide stops at the distalend of the catheter; a tubular member coupled to the base member andconfigured to apply a suction force from the catheter to an obstructionto remove the obstruction from the vasculature; and an expandable membersurrounding the tubular member. The expandable member is configured totransition from a contracted state to an expanded state after theexpandable member is at least partially extended into the vasculaturefrom the distal end of the catheter. The expandable member is furtherconfigured to at least partially surround the obstruction as theobstruction is being removed from the vasculature.

In one or more embodiments, a method of removing an obstruction from avasculature may include the steps of: (i) inserting a catheter into avasculature, the catheter having one or more guide stops located at adistal end of the catheter; (ii) inserting an obstruction removal devicethrough the catheter and at least partially extending the obstructionremoval device into the vasculature from the distal end of the catheter,the obstruction removal device including a base member that engages theone or more guide stops at the distal end of the catheter, theobstruction removal device further including an expandable member and atubular member; (iii) transitioning the expandable member from acontracted state to an expanded state after the expandable member is atleast partially extended into the vasculature from the distal end of thecatheter; and (iv) applying a suction force from the catheter to anobstruction, via the tubular member, to remove the obstruction from thevasculature, wherein the expandable member at least partially surroundsthe obstruction as the obstruction is being removed from thevasculature.

This Summary is provided solely as an introduction to subject matterthat is fully described in the Detailed Description and Drawings. TheSummary should not be considered to describe essential features nor beused to determine the scope of the Claims. Moreover, it is to beunderstood that both the foregoing Summary and the following DetailedDescription are example and explanatory only and are not necessarilyrestrictive of the subject matter claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. The use of the same reference numbers in different instances inthe description and the figures may indicate similar or identical items.Various embodiments or examples (“examples”) of the present disclosureare disclosed in the following detailed description and the accompanyingdrawings. The drawings are not necessarily to scale. In general,operations of disclosed processes may be performed in an arbitraryorder, unless otherwise provided in the claims.

FIG. 1A illustrates a cross-sectional side view of one or more cathetersof an obstruction removal system deployed within a vasculature, inaccordance with one or more embodiments of the present disclosure.

FIG. 1B illustrates a cross-sectional side view of an obstructionremoval device of the obstruction removal system being deployed througha catheter, wherein the obstruction removal device is pushed through thecatheter by a delivery wire/tube, in accordance with one or moreembodiments of the present disclosure.

FIG. 1C illustrates a cross-sectional side view of the obstructionremoval device being deployed through the catheter, wherein theobstruction removal device is pushed through the catheter by a deliverywire/tube, in accordance with one or more embodiments of the presentdisclosure.

FIG. 1D illustrates a cross-sectional side view of the obstructionremoval device being deployed through the catheter, wherein theobstruction removal device is pushed through the catheter by thedelivery wire/tube until a base member of the obstruction removal devicereaches one or more guide stops, in accordance with one or moreembodiments of the present disclosure.

FIG. 1E illustrates a cross-sectional side view of the obstructionremoval device being deployed through the catheter, wherein theobstruction removal device is pushed through the catheter by thedelivery wire/tube until a base member of the obstruction removal devicereaches one or more guide stops, and wherein an expandable member of theobstruction removal device transitions from a contracted state to anexpanded state when the obstruction removal device is extended from adistal end of the catheter, in accordance with one or more embodimentsof the present disclosure.

FIG. 1F illustrates a cross-sectional side view of the obstructionremoval device being deployed through the catheter in proximity of anobstruction within the vasculature, in accordance with one or moreembodiments of the present disclosure.

FIG. 1G illustrates a cross-sectional side view of the obstructionremoval device after being deployed through the catheter in proximity ofthe obstruction within the vasculature, wherein the delivery wire/tubeis removed and a suction force is applied from the catheter to suctionan obstruction from the vasculature via a tubular member of theobstruction removal device, and wherein the expandable member surroundsthe obstruction as the obstruction is being suctioned by the tubularmember, in accordance with one or more embodiments of the presentdisclosure.

FIG. 1H illustrates a cross-sectional side view of the obstructionremoval device and the catheter being drawn into a (larger) guidecatheter to remove the obstruction from the vasculature while theexpandable member surrounds the obstruction as the obstruction is beingsuctioned by the tubular member, in accordance with one or moreembodiments of the present disclosure.

FIG. 1I illustrates a cross-sectional side view of the obstructionremoval device and the catheter being drawn into the guide catheter toremove the obstruction from the vasculature while the expandable membersurrounds the obstruction as the obstruction is being suctioned by thetubular member, in accordance with one or more embodiments of thepresent disclosure.

FIG. 1J illustrates a cross-sectional side view of the obstructionremoval device and the catheter being pulled through the guide catheterto remove the obstruction from the vasculature while the expandablemember surrounds the obstruction as the obstruction is being suctionedby the tubular member, in accordance with one or more embodiments of thepresent disclosure.

FIG. 1K illustrates a cross-sectional side view of the obstructionremoval device after being deployed through the catheter in proximity ofthe obstruction within the vasculature, wherein the delivery wire/tubeis removed and a suction force is applied from the catheter to suctionan obstruction from the vasculature via a tubular member of theobstruction removal device, and wherein the expandable member surroundsthe obstruction as the obstruction is being suctioned by the tubularmember, in accordance with one or more embodiments of the presentdisclosure.

FIG. 1L illustrates a cross-sectional side view of the obstruction beingsuctioned from the vasculature via a tubular member of the obstructionremoval device, wherein the obstruction is at least partially brokenapart and suctioned into the catheter to remove the obstruction from thevasculature, in accordance with one or more embodiments of the presentdisclosure.

FIG. 1M illustrates a cross-sectional end view of a guide catheter withan aspiration catheter, intermediate catheter or microcatheter insertedwithin the guide catheter and a delivery tool inserted within theaspiration catheter, intermediate catheter or microcatheter, inaccordance with one or more embodiments of the present disclosure.

FIG. 1N illustrates a cross-sectional end view of aspiration catheter,intermediate catheter or microcatheter with guide stops attached to aninner surface of the aspiration catheter, intermediate catheter ormicrocatheter, in accordance with one or more embodiments of the presentdisclosure.

FIG. 1O illustrates a cross-sectional side view of the obstructionremoval device of the obstruction removal system, in accordance with oneor more embodiments of the present disclosure.

FIG. 1P illustrates a cross-sectional side view of the obstructionremoval device deployed through a catheter, wherein the one or moreguide stops are implemented by an indented or tapered portion of thecatheter having a smaller cross-sectional area than other portions(e.g., upstream portions) of the catheter, in accordance with one ormore embodiments of the present disclosure.

FIG. 2A illustrates a cross-sectional side view of a catheter of anobstruction removal system deployed within a vasculature, in accordancewith one or more embodiments of the present disclosure.

FIG. 2B illustrates a cross-sectional side view of an expandable memberof the obstruction removal system being deployed through the catheter,in accordance with one or more embodiments of the present disclosure.

FIG. 2C illustrates a cross-sectional side view of the expandable memberof the obstruction removal system being deployed through the catheteruntil a base member of the expandable member reaches one or more guidestops, wherein the expandable member is pushed through the catheter by adelivery wire/tube, in accordance with one or more embodiments of thepresent disclosure.

FIG. 2D illustrates a cross-sectional side view of the expandable memberof the obstruction removal system after being deployed through thecatheter until a base member of the expandable member reaches one ormore guide stops, wherein the delivery wire/tube is removed, and whereinthe expandable member transitions from a contracted state to an expandedstate when the expandable member is extended from a distal end of thecatheter, in accordance with one or more embodiments of the presentdisclosure.

FIG. 2E illustrates a cross-sectional side view of an agitator of theobstruction removal system being deployed through the catheter, whereinthe agitator is attached to a delivery tool that is fed through thecatheter using a microcatheter, in accordance with one or moreembodiments of the present disclosure.

FIG. 2F illustrates a cross-sectional side view of the agitator of theobstruction removal system being deployed through the catheter, whereinthe agitator attached to the delivery tool is fed through the catheterand the expandable member using the microcatheter, in accordance withone or more embodiments of the present disclosure.

FIG. 2G illustrates a cross-sectional side view of the obstructionremoval system deployed within the vasculature, wherein a suction forceis applied to the catheter to draw the obstruction through theexpandable member into the catheter, in accordance with one or moreembodiments of the present disclosure.

FIG. 2H illustrates a cross-sectional side view of the obstructionremoval system deployed within the vasculature, wherein a suction forceis applied to the catheter to draw the obstruction through theexpandable member into the catheter, and wherein the agitator is used tobreak apart the obstruction as the obstruction is being suctionedthrough the expandable member into catheter to remove the obstructionfrom the vasculature, in accordance with one or more embodiments of thepresent disclosure.

FIG. 2I illustrates a cross-sectional end view of a catheter with amicrocatheter inserted within the catheter and a delivery tool insertedwithin the microcatheter, in accordance with one or more embodiments ofthe present disclosure.

FIG. 2J illustrates a cross-sectional end view of a catheter with guidestops attached to an inner surface of the catheter, in accordance withone or more embodiments of the present disclosure.

FIG. 2K illustrates a cross-sectional side view of the expandable memberof the obstruction removal system, in accordance with one or moreembodiments of the present disclosure.

FIG. 2L illustrates a cross-sectional side view of the expandable memberof the obstruction removal system, in accordance with one or moreembodiments of the present disclosure.

FIG. 2M illustrates a cross-sectional side view of the expandable memberof the obstruction removal system, in accordance with one or moreembodiments of the present disclosure.

FIG. 3A illustrates a cross-sectional side view of a catheter of anobstruction removal system deployed within a vasculature, in accordancewith one or more embodiments of the present disclosure.

FIG. 3B illustrates a cross-sectional side view of an expandable memberof the obstruction removal system being deployed through the catheter,in accordance with one or more embodiments of the present disclosure.

FIG. 3C illustrates a cross-sectional side view of the expandable memberof the obstruction removal system being deployed through the catheteruntil a base member of the expandable member reaches one or more guidestops, wherein the expandable member is pushed through the catheter by adelivery wire/tube, in accordance with one or more embodiments of thepresent disclosure.

FIG. 3D illustrates a cross-sectional side view of the expandable memberof the obstruction removal system being deployed through the catheteruntil a base member of the expandable member reaches one or more guidestops, wherein the delivery wire/tube is removed, and wherein theexpandable member transitions from a collapsed state to an expandedstate when the expandable member is extended from a distal end of thecatheter, in accordance with one or more embodiments of the presentdisclosure.

FIG. 3E illustrates a cross-sectional side view of a stentriever of theobstruction removal system being deployed through the catheter, whereinthe stentriever is attached to a delivery tool that is fed through thecatheter using a microcatheter, in accordance with one or moreembodiments of the present disclosure.

FIG. 3F illustrates a cross-sectional side view of the stentriever ofthe obstruction removal system being deployed through the catheter,wherein the stentriever attached to the delivery tool is fed through thecatheter and the expandable member using the microcatheter, inaccordance with one or more embodiments of the present disclosure.

FIG. 3G illustrates a cross-sectional side view of the stentriever ofthe obstruction removal system being deployed within the vasculature,wherein the microcatheter is pulled back to unsheathe the stentriever sothat the stentriever can engage an obstruction in the vasculature, inaccordance with one or more embodiments of the present disclosure.

FIG. 3H illustrates a cross-sectional side view of the stentriever ofthe obstruction removal system being drawn into the catheter to removethe obstruction from the vasculature, in accordance with one or moreembodiments of the present disclosure.

FIG. 3I illustrates a cross-sectional side view of the stentriever ofthe obstruction removal system being drawn into the catheter to removethe obstruction from the vasculature, in accordance with one or moreembodiments of the present disclosure.

FIG. 3J illustrates a cross-sectional side view of the expandable memberof the obstruction removal system being pulled through the catheter withthe stentriever, wherein the expandable member transitions to acontracted state and surrounds at least a portion of the obstruction asthe expandable member is pulled into the catheter, in accordance withone or more embodiments of the present disclosure.

FIG. 3K illustrates a cross-sectional end view of a catheter with amicrocatheter inserted within the catheter and a delivery tool insertedwithin the microcatheter, in accordance with one or more embodiments ofthe present disclosure.

FIG. 3L illustrates a cross-sectional end view of a catheter with guidestops attached to an inner surface of the catheter, in accordance withone or more embodiments of the present disclosure.

FIG. 4A illustrates a cross-sectional side view of an aspirationcatheter and a guide catheter of an obstruction removal system deployedwithin a vasculature, wherein the aspiration catheter includes anexpandable member surrounding a portion of the aspiration catheter neara distal end of the aspiration catheter, in accordance with one or moreembodiments of the present disclosure.

FIG. 4B illustrates a cross-sectional side view the aspiration catheterbeing deployed through the guide catheter to engage an obstructionwithin the vasculature, in accordance with one or more embodiments ofthe present disclosure.

FIG. 4C illustrates a cross-sectional side view the expandable memberinverting as the aspiration catheter applies a suction force to theobstruction within the vasculature, in accordance with one or moreembodiments of the present disclosure.

FIG. 4D illustrates a cross-sectional side view the expandable memberinverted over the distal end of the aspiration catheter and at least aportion of the obstruction, which is held to the distal end of theaspiration catheter by the suction force, in accordance with one or moreembodiments of the present disclosure.

FIG. 4E illustrates a cross-sectional side view of the aspirationcatheter being drawn into the guide catheter to remove the obstructionfrom the vasculature while the expandable member surrounds theobstruction, which is being suctioned by the aspiration catheter, inaccordance with one or more embodiments of the present disclosure.

FIG. 4F further illustrates a cross-sectional side view of theaspiration catheter being drawn into the guide catheter to remove theobstruction from the vasculature while the expandable member surroundsthe obstruction, which is being suctioned by the aspiration catheter, inaccordance with one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to the subject matter disclosed,which is illustrated in the accompanying drawings.

Referring now to FIGS. 1A through 1P, an obstruction removal system isdescribed, in accordance with one or more embodiments of thisdisclosure. In particular, FIGS. 1A through 1P illustrate embodiments ofan obstruction removal system configured to deploy an obstructionremoval device including an expandable member within a vasculature toreduce the risks associated with removal of an obstruction when theobstruction is suctioned into and/or pulled through a catheter to removethe obstruction from the vasculature. The expandable member may be usedto prevent an obstruction from passing to a potentially more dangerousarea (e.g., causing a total blockage, blocking a portion of a vitalvasculature, etc.). In this regard, a physician may determine whether anobstruction is prone to risk and selectively deploy the expandablemember. Furthermore, the physician may deploy the expandable member atvarious locations away from the obstruction (e.g., clot), as needed.

In embodiments, the obstruction removal system includes a catheterconfigured to be inserted within a vasculature. The catheter may haveone or more guide stops located at a distal end of the catheter. Theobstruction removal system further includes an obstruction removaldevice that is configured to be inserted through the catheter and atleast partially extended into the vasculature from the distal end of thecatheter.

The obstruction removal device includes a base member configured toengage the one or more guide stops at the distal end of the catheter. Inembodiments, the obstruction removal device further includes a tubularmember coupled to the base member and configured to apply a suctionforce from the catheter to an obstruction to remove the obstruction fromthe vasculature. The obstruction removal device further includes anexpandable member surrounding the tubular member. The expandable memberis configured to transition from a contracted state to an expanded stateafter the expandable member is at least partially extended into thevasculature from the distal end of the catheter. The expandable memberis further configured to at least partially surround the obstruction asthe obstruction is being removed from the vasculature. In this manner,the expandable member helps prevent the obstruction (or portionsthereof) from being dislodged into the vasculature.

FIGS. 1A through 1P illustrate one or more embodiments of an obstructionremoval system 100. As shown in FIG. 1A, the obstruction removal system100 includes a catheter 114 (e.g., an aspiration catheter, intermediatecatheter, or the like) configured to be inserted through a vasculature102 to a position proximate to an obstruction 108. The obstructionremoval system 100 may include guide stops 104 attached (e.g., mounted)to or formed on an inner surface of the catheter 114, at or near adistal end of the catheter 114 (e.g., near an opening of the catheter).The obstruction removal system 100 may further include a guide catheter106 configured to be inserted through the vasculature 102 beforecatheter 114 so that catheter 114 can be fed through the guide catheter106.

In embodiments, the catheter 114 is configured to remove the obstruction108 from the vasculature 102 when a suction force is applied to thecatheter 114. For example, the catheter 114 may be coupled to a pump,syringe, vacuum chamber, or any other suction device configured toselectively produce negative pressure in the catheter 114 so that theobstruction 108 is drawn into (and/or suctioned onto) the catheter 114to remove the obstruction 108 from the vasculature 102.

As shown in FIG. 1B, the obstruction removal system 100 further includesan obstruction removal device 109 including an expandable member 110. Ina contracted state, the expandable member 110 is configured to beinserted through the catheter 114 and extended out of a distal openingof the catheter 114. When the expandable member 110 is in the contractedstate, the expandable member 110 may fit through the guide stops 104. InFIG. 1B, the expandable member 110 is illustrated in an orientationwhere the funnel/basket opening is forward facing while the expandablemember 110 is being fed through the catheter 114. However, in otherconfigurations, the expandable member 110 may be inserted through thecatheter 114 in an inverted orientation (where the funnel/basket openingtrails behind). In such cases, the expandable member 110 will invert sothat the funnel/basket opening is forward facing later on in theprocess. For example, the expandable member 110 may invert to look as itdoes in the drawings when the expandable member 110 is pulled back toremove the obstruction 108 from the vasculature 102 (i.e., during thesteps illustrated in FIGS. 1G through 1J).

FIG. 1C illustrates the expandable member 110 deployed out of the distalopening of the catheter 114, where a base member 112 attached to theexpandable member 110 is pushed up against, mated with, or otherwiseengages the guide stops 104. The delivery tool 120 can then be removed(e.g., withdrawn) from the catheter 114/vasculature 102. A delivery tool120 (e.g., a guide wire or tube) may be used to push the obstructionremoval device 109 with the expandable member 110 through the catheter114. In some embodiments, the delivery tool 120 may include anend-mounted support member 121 configured to support the obstructionremoval device 109 as the obstruction removal device 109 is pushedthrough the catheter 114.

FIGS. 1D through 1F illustrate the expandable member 110 of theobstruction removal device 109 transitioning to an expanded state. Inthe expanded state, the expandable member 110 may form a basket with afirst (proximal) opening that leads into the catheter 114 and a second(distal) opening that is configured to surround the obstruction 108while the obstruction 108 is being suctioned into the catheter 114 toremove the obstruction 108 from the vasculature 102. In this regard, thesecond (distal) opening is larger than the first (proximal) opening.

It is to be understood that the use of guide stops 104 on an innerportion of a catheter 114 may be suitable to allow a physician toselectively position the obstruction removal device 109 relative to theobstruction 108 by translating some portion of the catheter 114 and/orthe delivery tool 120. When positioning the catheter 114 and theobstruction removal device 109, the physician may account for suchthings as vasculature geometry, obstruction size, blood pressure, bloodflow direction, or vasculature tissue strength. For example, in someinstances, it may be undesirable to deploy the obstruction removaldevice 109 near the obstruction location (e.g., due to a complexvasculature structure) but may still be desirable to use the obstructionremoval device 109 (e.g., to reduce/control debris separated from theobstruction 108 when the obstruction is being removed from thevasculature 102). In this regard, the obstruction removal device 109 maybe deployed away from the obstruction 108 and still retain the benefitof reducing complications that may be caused by dislodgement or breakingup of the obstruction 108.

In embodiments, the obstruction removal device 109 further includes atubular member 116 coupled to the base member 112 and configured toapply a suction force from the catheter 114 to an obstruction 108 toremove the obstruction 108 from the vasculature 102. The expandablemember 110 surrounds the tubular member 116 and is configured totransition from a contracted state to an expanded state after theexpandable member 110 is at least partially extended into thevasculature 102 from the distal end of the catheter 114. Thus, theexpandable member 110 is configured to at least partially surround theobstruction 108 as the obstruction 108 is being removed from thevasculature 102. In this manner, the expandable 110 member helps preventthe obstruction 108 (or portions thereof) from being dislodged into thevasculature 102.

The tubular member 116 can be placed into contact with (or in closeproximity of) the obstruction 108 so that the obstruction 108 can besuctioned into the catheter 114 via the tubular member 116. In somecases, the obstruction 108 (or a portion thereof) may be too hard tosuction into the catheter 114; as a result, the obstruction 108 maybecome stuck onto the distal end of the tubular member 116 (e.g., asshown in FIG. 1G). When this occurs, the catheter 114 carrying theobstruction removal device 109 and obstruction 108 at its distal end canbe pulled out of the vasculature 102 through the guide catheter 106 toremove the obstruction 108 from the vasculature 102. As shown in FIGS.1H through 1J, the suction force holds the obstruction 108 to the distalend of the tubular member 116 while the expandable member 110 surroundsthe obstruction 108 so that the obstruction 108 can be safely pulledthrough the guide catheter 106 without dislodging or releasing anydebris into the vasculature 102.

As shown in FIGS. 1K and 1L, when the obstruction 108 is soft enough,the suction force will cause portions 107 of the obstruction 108 tobreak off or deform so that the obstruction 108 (or a portion thereof)is suctioned out of the vasculature 102 through the catheter 114. Insome cases, the obstruction 108 can be fully aspirated. In other cases,part of the obstruction 108 may be aspirated and the remainder of theobstruction 108 may be removed by pulling the catheter 114 carrying theobstruction removal device 109 and obstruction 108 at its distal endthrough the guide catheter 106 to remove the obstruction 108 from thevasculature 102, as described above with reference to FIGS. 1G through1J.

In some embodiments, the obstruction removal device 109 may have a wire113 coupled to the base member 112 and extended all the way through thecatheter 114. This wire 113 can prevent the obstruction removal device109 from being unintentionally ejected from the distal end of thecatheter 114 should the base member 112 become disengaged from the guidestops 104. The wire 113 can also be used to withdraw the obstructionremoval device 109 from the vasculature 102 (i.e., by pulling the wire113 to remove the obstruction removal device 109 by pulling it throughthe catheter 114).

FIG. 1M illustrates a cross-sectional end view of an obstruction removalsystem, where the delivery tool 120 is inserted through catheter 114 andguide catheter 106, and FIG. 1N illustrates a cross-sectional end viewof the catheter 114 with guide stops 104 (e.g., one or more protrusionsor a ring) attached to an inner surface of the catheter 114. Thedepicted guide stops 104 are non-limiting examples of means for engaginga base member. Additional structures or geometries may be used withoutdeviating from the scope of this disclosure. The guide stops 104 may beconfigured to engage with the base member 112 attached to the expandablemember 110 (e.g., by taking up a portion of the cross-sectional area ofthe catheter 114). Additionally, the guide stops 104 may be configuredto take up a minimal cross-sectional area of the catheter 114, in orderto allow injection of radioactive dye. In some embodiments, the guidestops 104 may be further configured to mate with the base member 112 totemporarily lock it in place at the distal end of the catheter 114.

Referring now to FIG. 1P, in some embodiments, the one or more guidestops 104 may be implemented by an indented or tapered portion of thecatheter 114. For example, the indented/tapered portion 104 may have asmaller cross-sectional area than other portions (e.g., upstreamportions) of the catheter 114. In an example embodiment, theindented/tapered portion 104 may have a diameter of 0.067 inches, whilea majority of the catheter has a diameter of 0.071 inches, and the basemember 112 (e.g., a marker band) has a diameter of 0.069 inches. Thesevalues are provided as examples to show that the difference in diametermay be as small as a difference of 0.001 to 0.01 inches; however, othervalues/ranges may be appropriate.

In some embodiments, the indented/tapered portion 104 (or other guidestops 104) may be located at a distance from the distal end of thecatheter 114. For example, the distance from the distal end of thecatheter 114 may be in the range of 5 cm to 30 cm. To accommodate thisdistance, the obstruction removal device 109 may include an intermediateportion 115 between the base member 112 and the expandable member 110.In some embodiments, the intermediate portion 115 is part of the tubularmember 116. For example, the tubular member 116 may have a lengthgreater than the distance between the indented/tapered portion 104 (orother guide stops 104) and the distal end of the catheter 114. In otherembodiments, the intermediate portion 115 is formed by another tubularmember or a substantially tubular section of braid/mesh. If a braid/meshis used, the braid/mesh may be formed from the same material as theexpandable member 110; however, other materials (e.g., steel) may beused to reduce cost and/or achieve desired structural attributes (e.g.,strength, flexibility, rigidity, etc.).

Referring generally to embodiments of the obstruction removal system 100disclosed herein, the expandable member 110 may be configured totransition between a first configuration and a second configuration, orbetween a contracted state and an expanded state, in any number of ways,including, but not limited to, unsheathing (e.g., extension throughcatheter 114), disengagement of locking members (e.g., wires, hooks,etc.) attached to the expandable member 110, use of shape memory alloys(e.g., Nitinol), or the like. It is envisioned that when the expandablemember is in an expanded state, the expandable member may take up asubstantial portion (e.g., 80% or more) of the cross-section of thevasculature 102.

In embodiments, the expandable member 110 may comprise a wire mesh. Sucha wire mesh may include wires made of a flexible material (e.g.,nitinol, cobalt chromium, polymer mesh, or the like), where the wires(e.g., 16 to 288 or more wires), have a certain diameter (e.g., from0.0007 inches to 0.0050 inches), and have certain material properties(e.g., strength, coefficient of friction with blood, resistance toplastic deformation, etc.) suitable for engaging the obstruction 108.Furthermore, the wire mesh may include various sets of wires (e.g.,support wires with larger diameters, wires to engage a vessel wall,wires to engage a portion of the obstruction or stentriever, radiopaqueor radiodense wires, etc.).

FIG. 1O is a cross-sectional side view illustrating the obstructionremoval device 109, in accordance with one or more embodiments of thisdisclosure. As noted above, the expandable member 110 forms a basket atthe distal end of the catheter 114 after transitioning from a contractedstate to an expanded state. The basket surrounds the tubular member 116so that the obstruction 108 is at least partially captured within thebasket when the obstruction 108 is being suctioned into the catheter 114and/or held against the tubular member 116 by the suction force. Thewire mesh that forms the expandable member 110 may be folded over itselfat a distal edge 120 of the basket to form an outer layer 122 and aninner layer 124 that are bound together at the base member 112. Foldingthe wire mesh over itself at the distal edge 120 of the basket may helpprevent stray wires that can snag on the vessel wall or cause damage thevasculature 102. In embodiments, the base member 112 may comprise anannular fitting (made from a molded structure or another mesh).Alternatively, the base member 112 can also be formed from a folded orrolled up a portion of the wire mesh.

A proximal portion 118 of the expandable member 110 may be configured tofold over the distal end of the catheter 114 in order to prevent theexpandable member 110 from being suctioned into the catheter 114. Insome embodiments, the expandable member 110 includes a narrow fold angleα between the proximal (smaller) opening of the basket and the proximalportion 118 of the basket. For example, the fold angle α may be in therange of 0 to 90 degrees, or possibly narrower (e.g., 0 to 45 degrees).Having a narrow fold angle α can help prevent the expandable member 110from being unintentionally suctioned into the catheter 114 when theobstruction 108 is being aspirated.

In embodiments, the tubular member 116 may be a flexible polymer tube;however, other tubing (e.g., a metal/glass tube) may also beappropriate. The tubular member 116 may be structurally reinforced by acoil 116 or by wire mesh. In other embodiments, the tubular member 116itself may be formed from wire mesh with sufficient density to maintainappropriate suction.

In some embodiments, the entire mesh or at least one of the layers(e.g., the outer layer 122 and/or the inner layer 124) may have a meshdensity selected to prevent or reduce fluid flow through the wire mesh(i.e., through layers/walls of the funnel). In other embodiments, theexpandable member 110 may alternatively, or additionally, include amembrane (e.g., a polymer membrane, or the like) disposed upon at leastone of the layers (e.g., the outer layer 122 and/or the inner layer 124)to prevent or reduce fluid flow through the wire mesh (i.e., throughlayers/walls of the funnel). In some embodiments, a membrane may bedisposed between the outer layer 122 and the inner layer 124 of thefunnel. In some embodiments, the membrane covers at least half (e.g.,50% to 100%) of the outer layer 122 and/or the inner layer 124. In otherembodiments, the membrane substantially covers (e.g., covers 80% to100%) of the outer layer 122 and/or the inner layer 124.

Any number of the presently disclosed elements may be suitable forimaging by a non-invasive imaging technology (e.g., X-ray, CT scans,etc.). For instance, the obstruction removal device 109 (or any portionthereof), guide catheter 106, catheter 114, delivery tool 120, and/orany additional components of the obstruction removal system 100 maycomprise radiodense or radiopaque material (e.g., titanium, tungsten,barium sulfate, or zirconium oxide) suitable for insertion in a humanbody.

It is to be understood that any number of components of the obstructionremoval system 100 may be attached by any suitable means including, butnot limited to, welding, adhesive, mechanical fastening, interferencefittings, etc. For example, the base member 112 may be attached to theexpandable member 110 by such means. Alternatively, or additionally, twoor more of the components may be portions of a common structure (e.g., acommon mold, print, or mesh structure).

In some embodiments, the obstruction removal device 109 is temporarilyattached to the delivery tool 120. For example, the obstruction removaldevice 109 may be configured to detach from the delivery tool 120 afterbase member 112 engages the one or more guide stops 104.

The base member 112 and guide stop(s) 104 may be configured toselectively engage and disengage. It is envisioned that the ability toselectively engage and disengage may provide advantages. For example,the ability to selectively disengage may allow for reusability of one ormore of the components (e.g., obstruction removal device 109, deliverytool 120, catheter 114, etc.). By way of another example, the ability toengage and disengage may provide increased functionality when insertingand removing components through the catheter 114 (e.g., fewer componentstranslating through the catheter 114 at the same time).

It is envisioned that there may be multiple orders in which one or moredevices of the obstruction removal system 100 are deployed. Factors fordetermining an order may include, but are not limited to, vasculatureproperties (e.g., vasculature size, vasculature geometries, branches ofthe vasculature, vasculature wall strength, etc.), blood pressure, bloodflow direction, duration of operation (i.e., does patient require areduced operating time for safety concerns), size of obstruction, or theconfiguration of the obstruction removal device.

Referring generally to FIGS. 1A through 1L, a method of removing anobstruction 108 from a vasculature 102 may include, but is not limitedto, the steps of: inserting a catheter 114 within a vasculature 102, thecatheter 114 having one or more guide stops 104 located at a distal endof the catheter 114 (FIG. 1A); inserting an obstruction removal device109 through the catheter 114 and at least partially extending theobstruction removal device 114 into the vasculature 102 from the distalend of the catheter 114, the obstruction removal device 109 including abase member 112 that engages the one or more guide stops 104 at thedistal end of the catheter 114, the obstruction removal device 109further including an expandable member 110 and a tubular member 116(FIGS. 1B and 1C); transitioning the expandable member 110 from acontracted state to an expanded state after the expandable member 110 isat least partially extended into the vasculature 102 from the distal endof the catheter 114 (FIGS. 1D and 1E); and applying a suction force fromthe catheter 114 to an obstruction 108, via the tubular member 116, toremove the obstruction 108 from the vasculature 102, wherein theexpandable member 110 at least partially surrounds the obstruction 108as the obstruction 108 is being removed from the vasculature 102 (FIG.1F and FIGS. 1K and 1L and/or FIGS. 1G through 1J). In implementations,the system 100 can be used in stages based on the situationalrequirements. For example, if aspiration fails or if only a portion ofthe obstruction 108 can be suctioned through the tubular member116/catheter 114 (FIGS. 1K and 1L), then the obstruction 108 orremainder of the obstruction 108 may be removed by pulling the catheter114 carrying the obstruction removal device 109 and obstruction 108 atits distal end through the guide catheter 106 to remove the obstruction108 from the vasculature 102, as described above with reference to FIGS.1G through 1J.

Referring now to FIGS. 2A through 2M, an obstruction removal system isdescribed, in accordance with one or more additional embodiments of thisdisclosure. In particular, FIGS. 2A through 2M illustrate embodiments ofan obstruction removal system configured to deploy an expandable memberin a vasculature to reduce the risks associated with removal of anobstruction when the obstruction is suctioned into the catheter toremove the obstruction from the vasculature. The expandable member maybe used to prevent an obstruction from passing to a potentially moredangerous area (e.g., causing a total blockage, blocking a portion of avital vasculature, etc.). In this regard, a physician may determinewhether an obstruction is prone to risk and selectively deploy theexpandable member. Furthermore, the physician may deploy the expandablemember at various locations away from the obstruction (e.g., clot), asneeded.

In embodiments, the obstruction removal system includes a catheterconfigured to be inserted within a vasculature. In embodiments, theobstruction removal device further includes a tubular member configuredto apply a suction force from the catheter to the obstruction to removethe obstruction from the vasculature. The expandable member surroundsthe tubular member and is configured to transition from a contractedstate to an expanded state after the expandable member is at leastpartially extended into the vasculature from the distal end of thecatheter. The expandable member is further configured to at leastpartially surround the obstruction as the obstruction is being removedfrom the vasculature.

FIGS. 2A through 2M illustrate one or more embodiments of an obstructionremoval system 200. As shown in FIG. 2A, the obstruction removal system200 includes a catheter 206 (e.g., an aspiration catheter, guidecatheter, intermediate catheter, or the like) configured to be insertedthrough a vasculature 202 to a position proximate to an obstruction 208.The obstruction removal system 200 may include guide stops 204 attached(e.g., mounted) to or formed on an inner surface of the catheter 206, ator near a distal end of the catheter 206 (e.g., near an opening of thecatheter).

In embodiments, the catheter 206 is configured to remove the obstruction208 from the vasculature 202 when a suction force is applied to thecatheter 206. For example, the catheter 206 may be coupled to a pump,syringe, vacuum chamber, or any other suction device configured toselectively produce negative pressure in the catheter 206 so that theobstruction 208 is drawn into the catheter 206 to remove the obstruction208 from the vasculature 202.

As shown in FIG. 2B, the obstruction removal system 200 further includesan expandable member 210. In a contracted state, the expandable member210 is configured to be inserted through the catheter 206 and extendedout of a distal opening of the catheter 206. When the expandable member210 is in the contracted state, the expandable member may fit throughthe guide stops 204.

FIG. 2C illustrates the expandable member 210 deployed out of the distalopening of the catheter 206, where a base member 212 attached to theexpandable member 210 is pushed up against, mated with, or otherwiseengages the guide stops 204. A delivery tool 220 (e.g., a guide wire ortube) may be used to push the expandable member 210 through the catheter206. In some embodiments, the delivery tool 220 may include anend-mounted support member 221 configured to support the expandablemember 210 as the expandable member 210 is pushed through the catheter206.

FIG. 2D illustrates the expandable member 210 transitioned to anexpanded state. The delivery tool 220 can then be removed (e.g.,withdrawn) from the catheter 206/vasculature 202. In the expanded state,the expandable member 210 may form a funnel with a first (proximal)opening that leads into the catheter 206 and a second (distal) openingthat is configured to receive the obstruction 208 when the obstruction208 is being suctioned into the catheter 206 to remove the obstruction208 from the vasculature 202. In this regard, the second (distal)opening is larger than the first (proximal) opening.

It is to be understood that the use of guide stops 204 on an innerportion of a catheter 206 may be suitable to allow a physician toselectively position the expandable member 210 at an appropriatedistance from an obstruction 208 by translating some portion of thecatheter 206 and/or the delivery tool 220. When positioning the catheter206 and the expandable member 210, the physician may account for suchthings as vasculature geometry, obstruction size, blood pressure, bloodflow direction, or vasculature tissue strength. For example, it may beundesirable to deploy the expandable member 210 near the obstructionlocation (e.g., due to a complex vasculature structure) but may still bedesirable to use the expandable member 210 (e.g., to reduce/controldebris separated from the obstruction 208 when the obstruction is beingremoved from the vasculature 202). In this regard, the expandable member210 may be deployed away from the obstruction 208 and still retain thebenefit of reducing complications that may be caused by dislodgement orbreaking up of the obstruction 208.

Referring now to FIG. 2E, the obstruction removal system 200 may furtherinclude an agitator 218 configured to be inserted through the catheter206. For example, the agitator 218 may be coupled or formed on/near adistal end of a delivery tool 216 (e.g., a guide wire or tube)configured to be inserted through the catheter 206. In some embodiments,the agitator 218 may be delivered through the catheter 206 using amicrocatheter 214 (e.g., any suitable microcatheter or delivery tube).The microcatheter 214 may be used to contain the agitator 218 and keepthe agitator 218 from expanding within the catheter 206. This mayprovide one or more advantages, such as, but not limited to, reducingfriction between the agitator 218 and the catheter 206, permitting theagitator 218 to be inserted through the base member 212 and/or thedistal opening of the catheter 206, and preventing the agitator 218 fromprematurely engaging with the expandable member 210. Alternatively, theagitator 218 may be guided through the catheter 206 by advancing thedelivery tool 216 without the use of a microcatheter 214.

FIG. 2F illustrates the agitator 218 inserted through the base member212, the expandable member 210, and the distal opening of the catheter206. The agitator 218 is attached to the delivery tool 216, so thatactuation of the delivery tool 216 results in actuation of the agitator218. For example, advancing or withdrawing the delivery tool 216 resultsin an advancement or withdrawal of the agitator 218, respectively. Thismay be performed manually, or alternatively, Alternatively, the deliverytool 216 may be coupled to a linear actuator configured to selectivelyactuate the delivery tool 216 forward and backward. In addition, theagitator 218 can be rotationally actuated (e.g., spun) by rotating thedelivery tool 216 clockwise or counterclockwise about its longitudinalaxis. The delivery tool 216 may be rotated manually (e.g., by spinningor twirling the delivery tool 216 between a user's fingers or by using acrank to rotate the delivery tool 216 about its longitudinal axis).Alternatively, the delivery tool 216 may be coupled to a rotationalactuator (e.g., a motor or servo) configured to rotate the delivery tool216 about its longitudinal axis.

In embodiments, the agitator 218 includes one or more wires configuredinto one or more loops, much like a mixer head (e.g., a whisk-like oreggbeater-like structure). Alternatively, or additionally, the agitator218 may include one or more wires or prongs that form one or more of: ahelical, spiral, or screw-like structure; a hook; a flat blade, acrossed blade, annular blade, or the like. In general, the agitator 218may have any structure that can engage an obstruction 208 to break apartor separate the obstruction into pieces.

FIG. 2G illustrates the agitator 218 deployed out of the distal end ofthe catheter 206 while the obstruction 208 is being suctioned into thecatheter 206. It is to be understood that there may be one or moremethods for engaging the obstruction 208 with the agitator 218. Forexample, the agitator 218 may engage the obstruction 208 when theobstruction 208 is at least partially surrounded by the expandablemember 210. Alternatively, the agitator 218 may be at least partiallyextended beyond the expandable member 210 to engage the obstruction 208before the obstruction 208 enters the expandable member 210.

As shown in FIG. 2H, the agitator 218 is used to break apart theobstruction 208 as the obstruction 208 is being suctioned, through thefunnel formed by the expandable member 210, into catheter 206 to removethe obstruction 208 from the vasculature 202. Smaller pieces 209 of theobstruction 208 are then suctioned into the catheter 206 to remove theobstruction 208 from the vasculature 202.

In embodiments, the expandable member 210 may be configured to preventcontact between the agitator 218 and a vessel wall of the vasculature202 when the agitator 218 is rotationally actuated (e.g., when theagitator is spinning). For example, the expandable member 210 and theagitator 218 may be configured to maintain a spatial relationship,wherein a widest portion of the agitator 218 is bound by the funnelformed by the expandable member 210 when the agitator 218 isrotationally actuated to prevent the agitator 218 from damaging thevasculature 202.

In some embodiments, the expandable member 210 has a wire (much likewire 113) coupled to the base member 212 and extended all the waythrough the catheter 206. This wire can prevent the expandable member210 from being unintentionally ejected from the distal end of thecatheter 206 should the base member 212 become disengaged from the guidestops 204. The wire can also be used to withdraw the expandable member210 from the vasculature 202 (i.e., by pulling the wire to remove theexpandable member 210 by pulling it through the catheter 206).

FIG. 2I illustrates a cross-sectional end view of an obstruction removalsystem, where the delivery tool 216 is inserted through microcatheter214 and catheter 206, and FIG. 2J illustrates a cross-sectional end viewof the catheter 206 with guide stops 204 (e.g., one or more protrusionsor a ring) attached to an inner surface of the catheter 206. Thedepicted guide stops 204 are non-limiting examples of means for engaginga base member. Additional structures or geometries may be used withoutdeviating from the scope of this disclosure. The guide stops 204 may beconfigured to engage with the base member 212 attached to the expandablemember 210 (e.g., by taking up a portion of the cross-sectional area ofthe catheter 206). Additionally, the guide stops 204 may be configuredto take up a minimal cross-sectional area of the catheter 206, in orderto allow injection of radioactive dye. In some embodiments, the guidestops 204 may be further configured to mate with the base member 212 totemporarily lock it in place at the distal end of the catheter 206.

Referring generally to embodiments of the obstruction removal system 200disclosed herein, the expandable member 210 may be configured totransition between a first configuration and a second configuration, orbetween a contracted state and an expanded state, in any number of ways,including, but not limited to, unsheathing (e.g., extension throughcatheter 206), disengagement of locking members (e.g., wires, hooks,etc.) attached to the expandable member 210, use of shape memory alloys(e.g., Nitinol), or the like. It is envisioned that when the expandablemember is in an expanded state, the expandable member may take up asubstantial portion (e.g., 80% or more) of the cross-section of thevasculature 202.

In embodiments, the expandable member 210 may comprise a wire mesh. Sucha wire mesh may include wires made of a flexible material (e.g.,nitinol, cobalt chromium, polymer mesh, or the like), where the wires(e.g., 16 to 288 or more wires), have a certain diameter (e.g., from0.0007 inches to 0.0050 inches), and have certain material properties(e.g., strength, coefficient of friction with blood, resistance toplastic deformation, etc.) suitable for engaging the obstruction 208and/or the agitator 218. Furthermore, the wire mesh may include varioussets of wires (e.g., support wires with larger diameters, wires toengage a vessel wall, wires to engage a portion of the obstruction orstentriever, radiopaque or radiodense wires, etc.).

FIGS. 2K through 2M are cross-sectional side views illustrating variousembodiments of the expandable member 210. As noted above, the expandablemember 210 forms a funnel at the distal end of the catheter 206 aftertransitioning from the contracted state to the expanded state. The wiremesh that forms the expandable member 210 may be folded over itself at adistal edge 226 of the funnel to form an outer layer 222 and an innerlayer 224 that are bound together at the base member 212. Folding thewire mesh over itself at the distal edge 226 of the funnel may helpprevent stray wires that can snag on the vessel wall or cause damage thevasculature 202. In embodiments, the base member 212 may comprise anannular fitting (made from a molded structure or another mesh).Alternatively, the base member 212 can also be formed from a fold orrolled up a portion of the wire mesh.

In some embodiments, the expandable member 210 includes a steeptransition angle θ between the proximal (smaller) opening of the funneland the distal (larger) opening of the funnel. For example, thetransition angle θ may be in the range of 90 to 120 degrees. Having asteep transition angle θ can help prevent the expandable member 210 frombeing unintentionally suctioned into the catheter 206 when theobstruction 208 is being removed from the vasculature 202.

The entire mesh or at least one of the layers (e.g., the outer layer 222and/or the inner layer 224) may have a mesh density selected to preventor reduce fluid flow through the wire mesh (i.e., through layers/wallsof the funnel). Otherwise, the funnel formed by the expandable member210 may not produce enough suction force within the vasculature 202 todraw the obstruction 208 into the funnel and then into the catheter 206.In some embodiments, the entire mesh or at least one of the layers(e.g., the outer layer 222 and/or the inner layer 224) may have a wiremesh density in the range of 48 to 144 wires/braid.

As shown in FIGS. 2L and 2M, the expandable member 210 mayalternatively, or additionally, include a membrane 222 (e.g., a polymermembrane, or the like) disposed upon at least one of the layers (e.g.,the outer layer 222 and/or the inner layer 224) to prevent or reducefluid flow through the wire mesh (i.e., through layers/walls of thefunnel). For example, FIG. 2L illustrates an embodiment of theexpandable member 210 with a membrane 228 disposed upon the outer layer222 of the funnel, and FIG. 2M illustrates an embodiment of theexpandable member 210 with a membrane 228 disposed between outer layer222 and the inner layer 224 of the funnel. In some embodiments, theexpandable member 210 may include a plurality of membranes 228 (e.g., amembrane 228 disposed upon the outer layer 222 of the funnel, andanother membrane 228 disposed between outer layer 222 and the innerlayer 224 of the funnel). In some embodiments, the membrane 228 coversat least half (e.g., 50% to 100%) of the outer layer 222 and/or theinner layer 224. In other embodiments, the membrane 228 substantiallycovers (e.g., covers 80% to 100%) of the outer layer 222 and/or theinner layer 224.

It noted that the membrane 228 is preferably between layers or outsidethe funnel formed by the expandable member 210 so that the agitator 218does not come into contact with (and possibly damage) the membrane 228.In some embodiments, the agitator 218 is fully or mostly bounded by theinner layer 224 of the expandable member 210, which may be formed fromnitinol, another metal, and/or another sufficiently durable material.Alternatively, the membrane 228 itself (if located on the inner surfaceof the funnel) may be formed from a sufficiently durable material sothat it cannot be shredded by the agitator 218.

Any number of the presently disclosed elements may be suitable forimaging by a non-invasive imaging technology (e.g., X-ray, CT scans,etc.). For instance, the catheter 206, microcatheter 214, delivery tool216, expandable member 210, agitator 218, guide stops 204, base member212 and/or any additional components may comprise radiodense orradiopaque material (e.g., titanium, tungsten, barium sulfate, orzirconium oxide) suitable for insertion in a human body.

It is to be understood that any number of components of the obstructionremoval system 200 may be attached by any suitable means including, butnot limited to, welding, adhesive, mechanical fastening, interferencefittings, etc. For example, the base member 212 may be attached to theexpandable member 210 by such means. Alternatively, or additionally, twoor more of the components may be portions of a common structure (e.g., acommon mold, print, or mesh structure).

In some embodiments, the expandable member 210 is temporarily attachedto the delivery tool 220. For example, the expandable member 210 may beconfigured to detach from the delivery tool 220 after base member 212engages the one or more guide stops 204.

The base member 212 and guide stop(s) 204 may be configured toselectively engage and disengage. It is envisioned that the ability toselectively engage and disengage may provide advantages. For example,the ability to selectively disengage may allow for reusability of one ormore of the components (e.g., expandable member 210, delivery tool 220,catheter 206, etc.). By way of another example, the ability to engageand disengage may provide increased functionality when inserting andremoving components through the catheter 206 (e.g., fewer componentstranslating through the catheter 206 at the same time).

It is envisioned that there may be multiple orders in which one or moredevices of the obstruction removal system 200 are deployed. Factors fordetermining an order may include, but are not limited to, vasculatureproperties (e.g., vasculature size, vasculature geometries, branches ofthe vasculature, vasculature wall strength, etc.), blood pressure, bloodflow direction, duration of operation (i.e., does patient require areduced operating time for safety concerns), size of obstruction, or theconfiguration of the obstruction removal device.

Referring generally to FIGS. 2A through 2H, a method of removing anobstruction 208 from a vasculature 202 may include, but is not limitedto, the steps of: inserting a catheter 206 within a vasculature 202, thecatheter 206 having one or more guide stops 204 located at a distal endof the catheter 206 (FIG. 2A); inserting an expandable member 210through the catheter 206 and at least partially extending the expandablemember 210 into the vasculature 202 from the distal end of the catheter206, the expandable member 210 including a base member 212 configured toengage the one or more guide stops 204 at the distal end of the catheter206 (FIGS. 2B and 2C); transitioning the expandable member 210 from acontracted state to an expanded state after the expandable member 210 isat least partially extended into the vasculature 202 from the distal endof the catheter 206 (FIGS. 2C and 2D); inserting an agitator 218 throughthe catheter 206 and at least partially extending the agitator 218 fromthe distal end of the catheter 206 (FIGS. 2E and 2F); suctioning anobstruction 208 from the vasculature 202 into the catheter 206, whereinthe expandable member 210 is configured to at least partially surroundthe obstruction 208 as the obstruction 208 is being suctioned into thecatheter 206 to remove the obstruction 208 from the vasculature 202(FIG. 2G); and breaking apart the obstruction 208 with the agitator 218as the obstruction 208 is being suctioned through the expandable member210 into catheter 206 to remove the obstruction 208 from the vasculature202 (FIG. 2H).

In some implementations, the system 200 can be used in stages based onthe situational requirements. For example, the catheter 206 mayinitially be used as a standalone catheter without the use of theexpandable member 210 or the agitator 218. For example, a user mayadvance the catheter 206 up to the proximal end of the obstruction 208.Then, a suction device connected to the catheter 206 may beactivated/actuated on to aspirate the obstruction 208. If aspirationfails, the expandable member 210 can be advanced through the catheter206 up to the distal end of the catheter 206. If aspiration fails again,the agitator 218 may then be advanced through the catheter 206 up to andinside the funnel formed by the expandable member 210. The agitator 218can be actuated back and forth and/or rotated within the funnel formedby the expandable member 210 to break up the obstruction 208 into smallpieces 209 so that the obstruction 208 (i.e., the pieces 209) can besuctioned into the catheter 206.

Although the agitator 218 is described with reference to system 200 andexpandable member 210, in other embodiments, the agitator 218 may beused in conjunction with other systems or devices described herein. Forexample, the obstruction removal device 109 in place of the expandablemember 210 illustrated in FIGS. 2A through 2M, or alternatively, theagitator 218 can be used in conjunction with system 100.

Referring now to FIGS. 3A through 3L, an obstruction removal system isdescribed, in accordance with one or more additional embodiments of thisdisclosure. In particular, FIGS. 3A through 3L illustrate embodiments ofan obstruction removal system configured to selectively deploy anexpandable member in a vasculature to reduce the risks associated withremoval of an obstruction. The expandable member may be used to preventan obstruction from dislodging from a stentriever and passing to apotentially more dangerous area (e.g., causing a total blockage,blocking a portion of a vital vasculature, etc.). In this regard, aphysician may determine whether an obstruction is prone to risk andselectively deploy the expandable member. Furthermore, the physician maydeploy the expandable member at various locations away from theobstruction (e.g., clot), as needed.

In embodiments, the obstruction removal system comprises a catheter(e.g., guide catheter, intermediate catheter, aspiration catheter, orthe like), a delivery tool (e.g., guide wire or tube), an expandablemember, and first and second locking members. The first locking membermay be attached to the base of the expandable member, such thatactuation of the expandable member results in actuation of the firstlocking member. The first locking member may be further configured toengage the second locking member. In this regard, the expandable membermay be fixed to the second locking member by the first locking member.

The expandable member may be inserted within the catheter by a deliverytool and/or microcatheter and disposed proximate to an obstruction inthe vasculature. The delivery tool and/or microcatheter may be furtherconfigured to engage the first locking member to the second lockingmember.

The expandable member may be configured to transition between one ormore positions, such as, a contracted state and an expanded state. Theexpanded state may allow the expandable member to surround a portion ofat least one of the stentriever and/or the obstruction. The contractedstate may be suitable for insertion and removal of the expandable memberthrough the catheter and/or a microcatheter. In this regard, when theexpandable member is in the collapsed/contracted state after surroundingat least a portion of the stentriever and/or the obstruction, theexpandable member, and the stentriever may be withdrawn through thecatheter and/or the microcatheter.

Benefits for surrounding a portion of the stentriever or the obstructionin an expandable member may include, but are not limited to, smallercross-sectional area, reduced friction on a vessel wall, reducedlikelihood of catching on an opening of the catheter, reduced likelihoodof catching on an opening of a microcatheter, and reduced likelihood ofobstruction dislodgement.

The expandable member is configured to transition between the one ormore positions (e.g., contracted state and collapsed position) in anysuitable way, including, but not limited to, internal stresses,friction, material properties, wires attached to the expandable member,hooks to grab on to/make contact with a portion of a vessel wall, or amating surface between the first locking member and the second lockingmember.

In some embodiments, the first locking member may be configured todisengage from the second locking member when the delivery system isremoved from the vasculature. In this regard, the disengagement of thefirst locking member from the second locking member may be used toremove the stentriever and obstruction from the vasculature. The abilityto disengage the first and second locking member may allow reuse of thedelivery tool, the stentriever, the expandable member, the catheter,and/or the microcatheter. The first and second locking member may engageby any suitable means, including but not limited to, guide stops,snap-fit connectors, cooperatively threaded connectors, magneticconnectors, or the like.

In embodiments, the second locking member may be attached in severallocations, including, but not limited to, the stentriever, the deliverytool, or an inner surface of the catheter. In this regard, after thefirst and second locking member engage, the first and second lockingmember will be fixed relative to the stentriever, the delivery tool, orthe catheter.

It is to be understood that the first and second locking member may beconfigured to engage at various points during the removal of theobstruction from the vasculature. For example, the first and secondlocking member may engage before or after the stentriever engages theobstruction. The order of engagement listed is not intended to belimiting.

FIGS. 3A through 3K illustrate one or more embodiments of an obstructionremoval system 300. As shown in FIG. 3A, the obstruction removal system300 includes a catheter 306 (e.g., guide catheter, intermediatecatheter, aspiration catheter, or the like) configured to be insertedthrough a vasculature to a position proximate to an obstruction 308. Theobstruction removal system 300 may include guide stops 304 attached(e.g., mounted) to or formed on an inner surface of the catheter 306, ator near a distal end of the catheter 306 (e.g., near an opening of thecatheter).

As shown in FIG. 3B, the obstruction removal system 300 further includesan expandable member 310. In a contracted state, the expandable member310 is configured to be inserted through the catheter 306 and extendedout of a distal opening of the catheter 306. When the expandable member310 is in the contracted state, the expandable member may fit throughthe guide stops 304.

FIG. 3C illustrates the expandable member 310 deployed out of the distalopening of the catheter 306, where a base member 312 attached to theexpandable member 310 is pushed up against, mated with, or otherwiseengaged with the guide stops 304. A delivery tool 320 (e.g., a guidewire or tube) may be used to push the expandable member 310 through thecatheter 306. In some embodiments, the delivery tool 320 may include anend-mounted support member 321 configured to support the expandablemember 310 as the expandable member 310 is pushed through the catheter306.

FIG. 3D illustrates the expandable member 310 transitioned to anexpanded state. The delivery tool 320 can then be removed (e.g.,withdrawn) from the catheter 306/vasculature 302. In the expanded state,the expandable member 310 may form a funnel with a first (proximal)opening that leads into the catheter 306 and a second (distal) openingthat is configured to receive the obstruction 308 when the obstruction308 is being removed from the vasculature 302. In this regard, thesecond (distal) opening is larger than the first (proximal) opening.

It is to be understood that the use of guide stops 304 on an innerportion of a catheter 306 may be suitable to allow a physician toselectively position the expandable member 310 at an appropriatedistance from an obstruction 308 by translating some portion of thecatheter 306 and/or the delivery tool 320. When positioning the catheter306 and the expandable member 310, the physician may account for suchthings as vasculature geometry, obstruction size, blood pressure, bloodflow direction, or vasculature tissue strength. For example, it may beundesirable to deploy the expandable member 310 near the obstructionlocation (e.g., due to a complex vasculature structure) but may still bedesirable to use the expandable member 310 (e.g., to reduce likelihoodof separation of the obstruction 308 from a stentriever). In thisexample, the expandable member 310 may be deployed away from theobstruction 308 and still retain the benefit of reducing complicationsdue to obstruction dislodgement.

Referring now to FIG. 3E, the obstruction removal system 300 may furtherinclude a stentriever 318 configured to be inserted through the catheter306. For example, the stentriever 318 may be coupled or formed on/near adistal end of a delivery tool 316 (e.g., guide wire or tube) configuredto be inserted through the catheter 306. In embodiments, the stentriever318 may be housed within a microcatheter 314 (e.g., any suitablemicrocatheter or delivery tube). The microcatheter 314 may be used tocontain the stentriever 318 and keep the stentriever 318 from expandingwithin the catheter 306. This may provide one or more advantages, suchas, but not limited to, reducing friction between the stentriever 318and the catheter 306, permitting the stentriever 318 to be insertedthrough the base member 312 and/or the distal opening of the catheter306, and preventing the stentriever 318 from prematurely engaging withthe expandable member 310.

FIG. 3F illustrates the stentriever 318, microcatheter 314, and deliverytool 316 inserted through the base member 312, the expandable member310, and the distal opening of the catheter 306. The stentriever 318 isattached to the delivery tool 316, so that actuation of the deliverytool 316 results in actuation of the stentriever 318.

FIG. 3G illustrates the stentriever 318 after the stentriever 318 hasbeen deployed out of a distal end of the microcatheter 314 and at leastpartially engaging the obstruction 308. It is to be understood thatthere may be one or more methods for engaging the obstruction 308 withthe stentriever 318. For example, the microcatheter 314 may be deployedthrough/alongside of the obstruction 308, with the stentriever 318contained within the microcatheter 314. The microcatheter 314 may thenbe withdrawn, permitting the stentriever 318 to expand and engage theobstruction 308.

FIGS. 3H and 3I illustrate the delivery tool 316 withdrawing thestentriever 318 (and the obstruction 308) towards the expandable member310. The expandable member 310 may be configured in an expanded state,such that the expandable member 310 may surround at least a portion ofthe obstruction 308 and/or stentriever 318 as the stentriever 318 andthe obstruction 308 are pulled into the catheter 306. As the deliverytool 316 is withdrawn and removed from the vasculature, the expandablemember 310 may transition from the expanded state to acontracted/collapsed state, thereby causing the expandable member 310 toat least partially surround and clench the obstruction 308 so that theobstruction 308 can be safely removed from the vasculature.

FIG. 3J illustrates the expandable member 310 withdrawn into thecatheter 306 in a collapsed position. In some embodiments, the basemember 312 may be configured to disengage from the guide stops 304. Thedelivery tool 316 with the stentriever 318, obstruction 308, andexpandable member 310 may be withdrawn through the microcatheter 314, asdepicted in FIG. 3J. Alternatively, the delivery tool 316 with thestentriever 318, obstruction 308, and expandable member 310 may bepulled directly through the catheter 306.

In some embodiments, the expandable member 310 has a wire (much likewire 113) coupled to the base member 312 and extended all the waythrough the catheter 306. This wire can prevent the expandable member310 from being unintentionally ejected from the distal end of thecatheter 306 should the base member 312 become disengaged from the guidestops 304. The wire can also be used to withdraw the expandable member310 from the vasculature 302 (i.e., by pulling the wire to remove theexpandable member 310 by pulling it through the catheter 306).

FIG. 3K illustrates a cross-sectional end view of an obstruction removalsystem, where a delivery tool 316 is inserted through a microcatheter314 and a catheter 306, and FIG. 3L illustrates a cross-sectional endview of a catheter 306 with guide stops 304 (e.g., one or moreprotrusions or a ring) attached to an inner surface of the catheter 306.The depicted guide stops 304 are non-limiting examples of means forengaging a base member. Additional structures or geometries may be usedwithout deviating from the scope of this disclosure. The guide stops 304may be configured to engage with a base member 312 attached to anexpandable member 310 (e.g., by taking up a portion of thecross-sectional area of the catheter 306). Additionally, the guide stops304 may be configured to take up a minimal cross-sectional area of thecatheter 306, in order to allow injection of radioactive dye. In someembodiments, the guide stops 304 may be further configured to mate withthe base member 312 to temporarily lock it in place at the distal end ofthe catheter 306.

Referring generally to embodiments of the obstruction removal system 300disclosed herein, the expandable member 310 may be configured totransition between a first configuration and a second configuration, orbetween a contracted state and an expanded state, in any number of ways,including, but not limited to, unsheathing (e.g., withdrawal of themicrocatheter 314 or extension through the catheter 306), disengagementof locking members (e.g., wires, hooks, etc.) attached to the expandablemember 310, use of shape memory alloys (e.g., Nitinol), or the like. Itis envisioned that when the expandable member is in an expanded state,the expandable member may take up a substantial portion (e.g., 80% ormore) of the cross-section of the vasculature 302.

In embodiments, the expandable member 310, the obstruction 308, and thestentriever 318 are withdrawn into the catheter 306 and removed from thevasculature. In some embodiments, the expandable member 310, theobstruction 308, and the stentriever 318 may be further withdrawn intothe microcatheter 314. The expandable member 310 may surround at least aportion of the obstruction 308 to prevent dislodging and may also assistin compressing the obstruction 308 into the catheter 306 and/or themicrocatheter 314 (e.g., by tension, cinching, crimping, etc.).

In some embodiments, an expandable member 310 may further include one ormore features including, but not limited to, hooks. The hooks may attachto or make abrasive contact with a vessel wall when the expandablemember 310 is in the expanded state; the hooks may also hold a portionof the obstruction 308 when the expandable member 310 at least partiallysurrounds the obstruction 308 prior to its removal.

Surrounding at least a portion of the obstruction 308 and/or stentriever318 by the expandable member 310 may serve several functions including,but not limited to, reducing a likelihood that the stentriever 318 snags(e.g., on a vessel wall of the vasculature 302 or an opening of thecatheter 306), reducing a profile of the obstruction 308 for removalthrough the catheter 306 and/or microcatheter 314, and/or securing theobstruction 308 to prevent dislodgement from the stentriever 318.

In embodiments, the expandable member 310 may comprise a wire mesh. Sucha wire mesh may include wires made of a flexible material (e.g.,nitinol, cobalt chromium, polymer mesh, or the like), where the wires(e.g., 16 to 288 or more wires), have a certain diameter (e.g., from0.0007 inches to 0.0050 inches), and have certain material properties(e.g., strength, coefficient of friction with blood, resistance toplastic deformation, etc.) suitable for engaging the obstruction 308and/or the stentriever 318. Furthermore, the wire mesh may includevarious sets of wires (e.g., support wires with larger diameters, wiresto engage a vessel wall, wires to engage a portion of the obstruction orstentriever, radiopaque or radiodense wires, etc.).

Any number of the presently disclosed elements may be suitable forimaging by a non-invasive imaging technology (e.g., X-ray, CT scans,etc.). For instance, the catheter 306, delivery tool 316, microcatheter314, expandable member 310, stentriever 318, guide stops 304, basemember 312 and/or any additional components may comprise radiodense orradiopaque material (e.g., titanium, tungsten, barium sulfate, orzirconium oxide) suitable for insertion in a human body.

It is to be understood that any number of components of the obstructionremoval system 300 may be attached by any suitable means including, butnot limited to, welding, adhesive, mechanical fastening, interferencefittings, etc. For example, the base member 312 may be attached to theexpandable member 310 by such means. Alternatively, or additionally, twoor more of the components may be portions of a common structure (e.g., acommon mold or print).

In some embodiments, the expandable member 310 is temporarily attachedto the microcatheter 314. For example, the expandable member 310 may beconfigured to detach from the microcatheter 314 after base member 312engages the one or more guide stops 304.

The base member 312 and guide stop(s) 304 may be configured toselectively engage and disengage. It is envisioned that the ability toselectively engage and disengage may provide advantages. For example,the ability to selectively disengage may allow for reusability of one ormore of the components (e.g., expandable member 310, microcatheter 314,catheter 306, etc.). By way of another example, the ability to engageand disengage may provide increased functionality when inserting andremoving components through the catheter 306 (e.g., fewer componentstranslating through the catheter 306 at the same time).

It is envisioned that there may be multiple orders in which one or moredevices of the obstruction removal system 300 are deployed. Factors fordetermining an order may include, but are not limited to, vasculatureproperties (e.g., vasculature size, vasculature geometries, branches ofthe vasculature, vasculature wall strength, etc.), blood pressure, bloodflow direction, duration of operation (i.e., does patient require areduced operating time for safety concerns), size of obstruction, or theconfiguration of the obstruction removal device.

Referring generally to FIGS. 3A through 3J, a method of removing anobstruction from a vasculature may include, but is not limited to, thesteps of: deploying the catheter 306 through the patient's vasculatureto a position near the obstruction 308, where the catheter 306 includesone or more guide stops 304 on an inner surface at the distal end of thecatheter 306; inserting the expandable member 310 through the catheter306 and (with a delivery tool 320) pushing the expandable member 310 upto the distal end of the catheter 306, so that a base member 312attached to the expandable member 310 engages the guide stops 304;inserting the stentriever 318 attached to delivery tool 316 within amicrocatheter 314 and feeding the stentriever 318 through the catheter306 using the microcatheter 314; deploying the stentriever 318 and themicrocatheter 314 through the catheter 306, guide stops 304, andexpandable member 310 up to the obstruction 308; withdrawing themicrocatheter 314 to unsheathe the stentriever 318 in order to engagethe obstruction 308 with the stentriever 318; withdrawing thestentriever 318 and the obstruction 308 by withdrawing (e.g., pulling)the delivery tool 316, where the expandable member 310 surrounds atleast a portion of the obstruction 308 and/or the stentriever 318 andtransitions from an expanded state to a contracted state as the deliverytool 316 with the stentriever 318 and obstruction 308 are pulled throughthe catheter 306 and removed from the vasculature.

Referring now to FIGS. 4A through 4F, an obstruction removal system isdescribed, in accordance with one or more additional embodiments of thisdisclosure. In particular, FIGS. 4A through 4F illustrate embodiments ofan obstruction removal system configured to deploy an expandable memberwithin a vasculature to reduce the risks associated with removal of anobstruction when the obstruction is suctioned into and/or pulled througha catheter to remove the obstruction from the vasculature. Theexpandable member may be used to prevent an obstruction from passing toa potentially more dangerous area (e.g., causing a total blockage,blocking a portion of a vital vasculature, etc.). In this regard, aphysician may determine whether an obstruction is prone to risk andselectively deploy the expandable member. Furthermore, the physician maydeploy the expandable member at various locations away from theobstruction (e.g., clot), as needed.

In embodiments, the obstruction removal system includes a catheterconfigured to be inserted within a vasculature. The catheter includes anexpandable member surrounding a portion of the catheter that is near adistal end of the catheter. The expandable member may be introduced intothe vasculature when the catheter (e.g., an aspiration catheter) isextended into the vasculature to engage and remove an obstruction (e.g.,using suction force). The expandable member may be configured to invertfrom a first orientation to a second orientation in order to cover thedistal end of the catheter and the obstruction engaged by the distal endof the catheter. This action may occur before or while the catheter isbeing pulled back out of the vasculature to remove the obstruction,which is held to the catheter by suction force, from the vasculature. Inthis manner, the expandable member is further configured to at leastpartially surround the obstruction as the obstruction is being removedfrom the vasculature. The expandable member helps prevent theobstruction (or portions thereof) from being dislodged into thevasculature.

FIGS. 4A through 4F illustrate one or more embodiments of an obstructionremoval system 400. As shown in FIGS. 4A and 4B, the obstruction removalsystem 400 includes a catheter 404 (e.g., an aspiration catheter,intermediate catheter, or the like) configured to be inserted through avasculature 402 to a position proximate to an obstruction 408. Theobstruction removal system 400 may further include a guide catheter 406configured to be inserted through the vasculature 402 before catheter404 so that catheter 404 can be fed through the guide catheter 406.

In embodiments, the catheter 404 is configured to remove the obstruction408 from the vasculature 402 when a suction force is applied to thecatheter 404. For example, the catheter 404 may be coupled to a pump,syringe, vacuum chamber, or any other suction device configured toselectively produce negative pressure in the catheter 404 so that theobstruction 408 is drawn into (and/or suctioned onto) the catheter 404to remove the obstruction 408 from the vasculature 402.

The obstruction removal system 400 further includes an expandable member410 that is coupled to the catheter 404. In embodiments, the expandablemember 410 is a tubular or funnel shaped mesh with one free end and onefixed end that is affixed to the catheter 404 (e.g., by one or morefasteners 412, such as a marker band, glue, molding, welding, etc.) insuch a way that the expandable member 410 surrounds a portion of thecatheter 404 that is near a distal end of the catheter 404. In a firstorientation, the expandable member 410 trails behind the distal end ofthe catheter 404. For example, the expandable member 410 is configuredto trail behind the distal end of the catheter 404 while the catheter isbeing inserted through the guide catheter 406 and/or vasculature 402. Asshown in FIGS. 4C and 4D, the expandable member 410 is configured to beselectively inverted to a second orientation so the expandable member410 covers the distal end of the catheter 404 and surrounds at least aportion of the obstruction 408. For example, the expandable member 410may be inverted as a result of friction between the expandable member410 and the vasculature 402 or the fluid flowing therethrough when thecatheter 404 is pulled back through the guide catheter 406 and/orvasculature 402 in order to remove the catheter 404 and the obstruction408, which is being suctioned by the catheter 404, from the vasculature402.

FIGS. 4C and 4D illustrate the expandable member 410 transitioning(i.e., inverting) from a first orientation to a second orientation. Inthe second orientation (sometimes referred to as the “inverted state”),the expandable member 410 may form a basket or funnel with a first(proximal) opening that surrounds a portion of the catheter 404 and asecond (distal) opening that is configured to surround the obstruction408 while the obstruction 408 is being suctioned into the catheter 404to remove the obstruction 408 from the vasculature 402. In this regard,the second (distal) opening is larger than the first (proximal) opening.

It is to be understood that the use of a guide catheter 406 may allow aphysician to selectively position catheter 404 relative to theobstruction 408 by translating catheter 404 relative to the guidecatheter 406. When positioning the catheter 404 and the expandablemember 410, the physician may account for such things as vasculaturegeometry, obstruction size, blood pressure, blood flow direction, orvasculature tissue strength. For example, in some instances, it may beundesirable to deploy the expandable member 410 near the obstructionlocation (e.g., due to a complex vasculature structure) but may still bedesirable to use the expandable member 410 (e.g., to reduce/controldebris separated from the obstruction 408 when the obstruction is beingremoved from the vasculature 402). In this regard, the expandable member410 may be deployed away from the obstruction 408 and still retain thebenefit of reducing complications that may be caused by dislodgement orbreaking up of the obstruction 408.

In use, the obstruction removal system 400 is configured to apply asuction force from the catheter 404 to an obstruction 408 to remove theobstruction 408 from the vasculature 402. The expandable member 410surrounds a distal portion of the catheter 404 and is configured totransition from a first (trailing) orientation to an inverted stateafter the expandable member 410 is at least partially extended into thevasculature 402 and then pulled back (e.g., to withdraw the catheter404). The change in direction when the expandable member 410 is pulledback subjects the expandable member 410 to frictional forces (orresistive forces) resulting from contact with inner surfaces of thevasculature 402 or resistance from the fluid flowing therethrough. Afterinverting, the expandable member 410 is configured to at least partiallysurround the obstruction 408 as the obstruction 408 is being removedfrom the vasculature 402. In this manner, the expandable 410 memberhelps prevent the obstruction 408 (or portions thereof) from beingdislodged into the vasculature 402.

The catheter 404 can be placed into contact with (or in close proximityof) the obstruction 408 so that the obstruction 408 can be suctionedinto the catheter 414. In some cases, the obstruction 408 (or a portionthereof) may be too hard to suction into the catheter 404; as a result,the obstruction 408 may become stuck onto the distal end of the catheter404 (e.g., as shown in FIG. 4B). When this occurs, the catheter 404carrying the obstruction 408 at its distal end can be pulled out of thevasculature 402 through the guide catheter 406 to remove the obstruction408 from the vasculature 402. As shown in FIGS. 4C through 4F, thesuction force holds the obstruction 408 to the distal end of thecatheter 404 while the expandable member 410 inverts and surrounds theobstruction 408 so that the obstruction 408 can be safely pulled throughthe guide catheter 406 without dislodging or releasing any debris intothe vasculature 402.

In some embodiments, the catheter 404 has a narrow diameter so thatobstructions 408 are usually held at the distal end of the catheter 404rather than being sucked up through the catheter 404 as they wouldtypically be when using an aspiration catheter. This allows anobstruction 408 to be surrounded by the expandable member 410 andremoved by withdrawing the catheter 404 with the obstruction 408 throughthe guide catheter 406, thereby preventing potential dislodging orrelease of debris that could occur when the obstruction 408 is suctionedout of the vasculature 402 using a typical aspiration catheter.

Nevertheless, when the obstruction 408 is soft enough, the suction forcewill cause portions of the obstruction 408 to break off or deform sothat the obstruction 408 (or a portion thereof) is suctioned out of thevasculature 402 through the catheter 404. In some cases, the obstruction408 can be fully aspirated. In other cases, part of the obstruction 408may be aspirated and the remainder of the obstruction 408 may be removedby pulling the catheter 404 carrying the obstruction 408, surrounded bythe expandable member 410, at its distal end through the guide catheter406 to remove the obstruction 408 from the vasculature 402.

In some embodiments, the expandable member 410 may have a wire coupledto the expandable member 410 and extended all the way through the guidecatheter 406. This wire can prevent the expandable member 410 from beingunintentionally decoupled from the catheter 404. The wire can also beused to withdraw the expandable member 410 from the vasculature 402(i.e., by pulling the wire to remove the expandable member 410 bypulling it through guide catheter 406).

Referring generally to embodiments of the obstruction removal system 400disclosed herein, the expandable member 410 may be configured totransition between a first configuration (e.g., trailing orientation)and a second configuration (e.g., inverted orientation), or between acontracted state and an expanded state, in any number of ways,including, but not limited to, frictional or resistive forces resultingfrom contact with inner surfaces of the vasculature 402 or fluid flowingtherethrough, unsheathing (e.g., extension through the guide catheter406), disengagement of locking members (e.g., wires, hooks, etc.)attached to the expandable member 410, use of shape memory alloys (e.g.,Nitinol), or the like. It is envisioned that when the expandable memberis in an expanded/inverted state, the expandable member may take up asubstantial portion (e.g., 80% or more) of the cross-section of thevasculature 402.

In embodiments, the expandable member 410 may comprise a wire mesh. Sucha wire mesh may include wires made of a flexible material (e.g.,nitinol, cobalt chromium, polymer mesh, or the like), where the wires(e.g., 16 to 288 or more wires), have a certain diameter (e.g., from0.0007 inches to 0.0050 inches), and have certain material properties(e.g., strength, coefficient of friction with blood, resistance toplastic deformation, etc.) suitable for engaging the obstruction 408.Furthermore, the wire mesh may include various sets of wires (e.g.,support wires with larger diameters, wires to engage a vessel wall,wires to engage a portion of the obstruction or stentriever, radiopaqueor radiodense wires, etc.).

Any number of the presently disclosed elements may be suitable forimaging by a non-invasive imaging technology (e.g., X-ray, CT scans,etc.). For instance, the expandable member 410 (or any portion thereof),guide catheter 406, catheter 404, and/or any additional components ofthe obstruction removal system 400 may comprise radiodense or radiopaquematerial (e.g., titanium, tungsten, barium sulfate, or zirconium oxide)suitable for insertion in a human body.

It is to be understood that any number of components of the obstructionremoval system 400 may be attached by any suitable means including, butnot limited to, welding, adhesive, mechanical fastening, interferencefittings, etc. For example, the catheter 404 may be attached to theexpandable member 410 by such means. Alternatively, or additionally, twoor more of the components may be portions of a common structure (e.g., acommon mold, print, or mesh structure).

It is envisioned that there may be multiple orders in which one or moredevices of the obstruction removal system 400 are deployed. Factors fordetermining an order may include, but are not limited to, vasculatureproperties (e.g., vasculature size, vasculature geometries, branches ofthe vasculature, vasculature wall strength, etc.), blood pressure, bloodflow direction, duration of operation (i.e., does patient require areduced operating time for safety concerns), size of obstruction, or theconfiguration of the obstruction removal device.

Referring generally to FIGS. 4A through 4F, a method of removing anobstruction 408 from a vasculature 402 may include, but is not limitedto, the steps of: inserting a catheter 404 within a vasculature 402(directly or by introducing the catheter 404 through a guide catheter406), the catheter 404 having an expandable member surrounding a portionof the catheter 404 at or near a distal end of the catheter 404 (FIG.4A); engaging the obstruction 408 in the vasculature 402 with the distalend of the catheter 404 and suctioning the obstruction 408 into/onto thedistal end of the catheter 404 (FIG. 4B); inverting the expandablemember 410 to cover or surround the distal end of the catheter 404 andat least a portion of the obstruction 408 with the inverted expandablemember 410 (FIGS. 4C and 4D); and withdrawing the catheter 404 from thevasculature 402 (directly or through a guide catheter 406) to remove theobstruction 408, which is held onto the distal end of the catheter 404by suction force and at least partially surrounded by the expandablemember 410 (FIGS. 4E and 4F).

It is to be understood that implementations of the methods disclosedherein may include one or more of the steps described herein. Further,such steps may be carried out in any desired order and, in someimplementations, two or more of the steps may be carried outsimultaneously with one another. Two or more of the steps disclosedherein may be combined in a single step, and in some implementations,one or more of the steps may be carried out as two or more sub-steps.Further, other steps or sub-steps may be carried in addition to, or assubstitutes to one or more of the steps disclosed herein.

It is also to be understood that usage of terminology in the presentdisclosure is not intended to be limiting. For example, as used herein,an “obstruction” may refer to any vascular obstruction, including butnot limited to, a blood clot, plaque (e.g., fat, cholesterol, etc.),internal structure/growth, foreign object, or the like.

Although the technology has been described with reference to theembodiments illustrated in the attached drawing figures, equivalents maybe employed, and substitutions may be made without departing from thescope of the technology as recited in the claims. Components illustratedand described herein are examples of a device and components that may beused to implement the embodiments of the present invention and may bereplaced with other devices and components without departing from thescope of the invention. Furthermore, any dimensions, degrees, and/ornumerical ranges provided herein are to be understood as non-limitingexamples unless otherwise specified in the claims.

What is claimed is:
 1. An obstruction removal system, comprising: acatheter configured to be inserted into a vasculature; one or more guidestops located at a distal end of the catheter; and an obstructionremoval device configured to be inserted through the catheter and atleast partially extended into the vasculature from the distal end of thecatheter, the obstruction removal device including: a base memberconfigured to engage the one or more guide stops at the distal end ofthe catheter; a tubular member coupled to the base member and configuredto apply a suction force from the catheter to an obstruction to removethe obstruction from the vasculature; and an expandable membersurrounding the tubular member, the expandable member being configuredto transition from a contracted state to an expanded state after theexpandable member is at least partially extended into the vasculaturefrom the distal end of the catheter, the expandable member being furtherconfigured to at least partially surround the obstruction as theobstruction is being removed from the vasculature, wherein a proximalportion of the expandable member is configured to fold over the distalend of the catheter in order to prevent the expandable member from beingsuctioned into the catheter.
 2. The obstruction removal system of claim1, wherein a distal portion of the expandable member is configured toform a basket around the tubular member to at least partially surroundthe obstruction as the obstruction is being removed from thevasculature.
 3. The obstruction removal system of claim 1, wherein thetubular member comprises a flexible polymer tube.
 4. The obstructionremoval system of claim 3, wherein the tubular member is structurallyreinforced by a coil or a wire mesh.
 5. The obstruction removal systemof claim 1, wherein the expandable member comprises a wire mesh foldedat a distal edge to form an outer layer and an inner layer that arebound together at the base member.
 6. The obstruction removal system ofclaim 1, further comprising: a guide catheter, wherein the catheter isconfigured to be inserted into the vasculature through the guidecatheter.
 7. The obstruction removal system of claim 6, wherein thecatheter and the obstruction removal device, carrying at least a portionof the obstruction surrounded by the expandable member, are configuredto be withdrawn from the vasculature through the guide catheter when theobstruction cannot be fully suctioned into the catheter through thetubular member.
 8. An obstruction removal device configured to beinserted through a catheter and at least partially extended into avasculature from a distal end of the catheter, the obstruction removaldevice comprising: a base member configured to engage one or more guidestops at the distal end of the catheter; a tubular member coupled to thebase member and configured to apply a suction force from the catheter toan obstruction to remove the obstruction from the vasculature; and anexpandable member surrounding the tubular member, the expandable memberbeing configured to transition from a contracted state to an expandedstate after the expandable member is at least partially extended intothe vasculature from the distal end of the catheter, the expandablemember being further configured to at least partially surround theobstruction as the obstruction is being removed from the vasculature,wherein a proximal portion of the expandable member is configured tofold over the distal end of the catheter in order to prevent theexpandable member from being suctioned into the catheter.
 9. Theobstruction removal device of claim 8, wherein a distal portion of theexpandable member is configured to form a basket around the tubularmember to at least partially surround the obstruction as the obstructionis being removed from the vasculature.
 10. The obstruction removaldevice of claim 8, wherein the tubular member comprises a flexiblepolymer tube.
 11. The obstruction removal device of claim 10, whereinthe tubular member is structurally reinforced by a coil or a wire mesh.12. The obstruction removal device of claim 8, wherein the expandablemember comprises a wire mesh folded at a distal edge to form an outerlayer and an inner layer that are bound together at the base member. 13.The obstruction removal device of claim 8, wherein the obstructionremoval device, carrying at least a portion of the obstructionsurrounded by the expandable member, is configured to be withdrawn fromthe vasculature with the catheter through a guide catheter when theobstruction cannot be fully suctioned into the catheter through thetubular member.